FeMn/Co thin-films, a purely metallic exchange-bias system,were prepared on (100)-oriented MgO single crystals. The layers were grown by molecular beam epitaxy (MBE). The crystalline and magnetic properties could be tuned by using sputtered Pt buffer layers deposited at variable temperatures. A transition of the crystalline orientation from (111)-terminated layers at lower deposition temperat…
The ever growing demand for wireless data communications is driving a need for new technologies to augment the existing radio frequency approaches (such as WiFi). Visible light communications (VLC) offers a means to do this, using the unlicensed visible region of the electromagnetic spectrum for wireless communications, where hundreds of terahertz of bandwidth are available. The adoption of l…
In this study, we investigate the formation of Mo(S,Se)2 layers in the interface region between the absorber and the back contact in electrodeposited CuIn(S,Se)2 (CISSe) solar cells, and its influence on the resulting devices. Mo(S,Se)2 layers are formed spontaneously in the Mo/CI(S,Se) interface during the annealing of the absorber, but have a serious impact on the solar cell performance, bein…
As a result of changes in the energy marketplace, the role of energy audits has greatly expanded. There is an increasing need in business and industry to more effectively man age energy use. Reducing utility costs is still one of the most effective and achievable strategies for lowering the operating costs. Today, many large energy consumers are contracting with energy service providers…
Gold nanocrystals and nanoassemblies have attracted extensive attention for various applications, including chemical and biological sensing, solar energy harvesting, and plasmon-enhanced spectroscopies, due to their unique plasmonic properties. It is of great importance to prepare shape-controlled Au nanocrystals with high monodispersity over a large range of sizes. In this work, Au nanosphere…
A project has been initiated in South Africa to design, model, build, and evaluate an easy to install solar fueled combined heat and power (micro-CHP) system to supply off-grid rural villages and eco-estate communities. This study describes the design of a model that offers a combined 3 kW peak electrical,12 kW peak thermal, stand-alone solar power technology solution with microgrid storage to…
A project has been initiated in South Africa to design, model, build, and evaluate an easy to install solar fueled combined heat and power (micro-CHP) system to supply off-grid rural villages and eco-estate communities. This study describes the design of a model that offers a combined 3 kW peak electrical,12 kW peak thermal, stand-alone solar power technology solution with microgrid storage to…
In order to improve the short-circuit current and the efficiency of silicon heterojunction solar cells, Ag grid/ITO/(p)a-Si:H/(i) a-Si:H/(n)c-Si/(i)a-Si:H/(nþ)a-Si:H/Al, ZnO nanostructured (NS) array films are deposited by electrochemical method on the front side of the solar cells. Aqueous solutions of ZnCl2 and KCl at temperature of 80 8C were used as electrolyte, employing a three-electrode…
In this work the processing sequence for an integrated interconnection concept for crystalline silicon thin-films (c-Si TF) is introduced. This concept is designed to reduce cost in the production of large-area crystalline silicon thin-film modules. Combining the advantages of classical thin-film and wafer technologies, a soldering-free interconnection of cells in the module is realized. In or…
High carrier mobility and tunability in graphene enable fundamental studies for plasmonics and various applications. Despite its versatility, however,single-layer graphene (SLG) suffers from poor coupling effi ciency to electromagnetic waves, presenting a major challenge for photonic applications.Compared with visible or infrared radiation, terahertz (THz) waves exhibit higher absorption in SL…
Quebec’s large solar power potential markedly contrasts with its poor achievements in using solar energy in this large and wealthy region of the world. Reviewing recent developments and putting discussion in the socioeconomic context, we provide arguments that justify our viewpoint that solar energy will soon be a relevant source of power in this Province of Canada. The rapid fall in price o…
We investigate the value of solar photovoltaic (PV) power in the Italian wholesale electricity market (IPEX). A model is developed and applied to simulate and predict the monthly average electricity prices in peak hours, as well as to simulate scenarios without PV generation. The computed merit-order effect of the PV generation in Italy, around 2.9 €/MWh per each additional GWh of PV produc…
This study presents comprehensive thermoeconomic and thermoenvironomic modeling and analysis of selected gas turbine power plants in Nigeria using the first and second laws of thermodynamics (exergy) concept. Exergetic analysis was conducted using operating data obtained from the power plants to determine the exergy destruction and exergy efficiency of each major component of the gas turbine i…
An effi cient tandem organic light-emitting diode is realized by employing a novel light out-coupling structure with deterministic quasi-periodic nanocone arrays. The enhancement of color spatial uniformity and operational stability is simultaneously realized along with the remarkable effi ciency improvement in tandem devices by integrating multi-photon emission and light out-coupling techniqu…
This article presents an overview of the fabrication methods of black silicon,their resulting morphologies, and a quantitative comparison of their optoelectronic properties. To perform this quantitative comparison, different groups working on black silicon solar cells have cooperated for this study. The optical absorption and the minority carrier lifetime are used as benchmark parameters.The d…
In recent times, hybrid renewable energy systems are increasingly being utilized to provide electricity in remote areas especially where the grid extension is considered too expensive. This study presents the results of techno-economic analysis of hybrid system comprising of solar and wind energy for powering a specific remote mobile base transceiver station (BTS) in Nigeria. All the necessary …
ZnO nanorod arrays placed within the architecture of the Cu(In,Ga)Se2 solar cell present promising concepts to maximize photoconversion by optical and electrical enhancement. Three different Cu(In,Ga)Se2 solar cell architectures utilizing ZnO nanorods are introduced. New technological insights are given for electrodeposited ZnO nanorod anti-reflection coatings,examining the reflectance of devi…
The energy supply characteristic of a proton-exchange membrane fuel cell for houses is strongly influenced in a hydrogen supply unit. Therefore, a bioethanol reforming system (FBSR) with a sunlight heat source is developed as a potential fuel supply system for distributed fuel cells. However, the temperature distribution of a catalyst layer in the reactor is not stable under conditions of unst…
In this article, we present performance results and analysis of a novel rotary lobe expander device. This is part of a larger research effort into the analysis and design of a small-scale solar system that would compete with available distributed technologies for heat and electricity generation. To choose an appropriate working fluid and components for a distributed concentrating solar combined…
The aim of this study was to estimate the reference level of cadmium in rice as the benchmark doses (BMD) and their 95% lower confidence limits (BMDL) for various renal effects by applying an updated hybrid approach. The participants were 1120 men and 1274 women aged 50 years or older who lived in the environmentally exposed Kakehashi river basin for at least 30 years. As indicators of renal d…
Organometal hybrid perovskites exhibit tunable absorption and photoluminescence spectra that originate from the adjustable excitons of the self-assembled quantum-well structures. The aggregation-induced emission (AIE) features of (RNH 3 ) 2 PbI 4 (R = alkyl, C n H 2 n +1 , n = 4, 12, 16, 18) as well as their reversible photoluminescence response to pH value are demonstrated.This interesting p…
A new irradiance adjustment system for the light source named “Programmable Reference cell system for Irradiance adjustment by Spectral Measurement (PRISM)” has been developed for photovoltaics evaluation. It can be applied for various kinds of solar cells and illumination conditions without the preparation of conventional reference cells. This system consists of a device for absolute spec…
Epidemiological studies indicate that exposure to diesel exhaust (DE) is associated with vascular-based disorders. To investigate the effect of DE on blood–brain barrier (BBB) function and integrity, 8-week-old BALB/c mice were randomized to DE in a cyclical treatment regimen over a 2-week period. Functional integrity of BBB was determined by considering brain parenchymal abundance of IgG wi…
Lignocellulosic feedstock has tremendous potential to sustain the renewable production of biofuels such as ethanol and butanol. Although lignocellulosic biomass is a storehouse of energy in the form of cellulose and hemicellulose, yet lignin acts as a barrier against their hydrolysis. A dilute acid pretreatment disintegrates the biomass complex and allows cellulolytic enzymes to hydrolyze cell…
ABSTRACT: The most potent chemicals potentially causing adverse effects on fish species are estrogens in human waste. Sewage is a source of these estrogens and it is difficult to reduce. In particular, although the bioactivity of estrone is estimated to be about half of that of estradiol, multiple studies report that more than 100 ng l–1 of estrone can be detected in urban rivers, including …
The rapid ascent of nanoscience has garnered signifi cant attention in recent years. Much of the interest generated has dealt with the integration of nanoparticles in various applications ranging from automotive and textiles to bioimaging and nanomedicine. In order for the realization of this potential,their synthesis and chemistry need to be thoroughly understood. One particularly interesting…
We investigate the stabilized performance of encapsulated hydrogenated amorphous silicon photovoltaic modules depending on the deposition speed. The module products are degraded differently depending on the light-soaking environment. The modules deposited at a high speed demonstrate significant degradation in an outdoor exposure test, despite moderate degradation during indoor light soaking. H…
Few-layer MoSe2 granular films were prepared using rapid thermal processing (RTP) of stacked elemental layers (SELs) deposited using electron beam evaporation in the sequence of Mo/Se/Mo. RTP was carried out at various temperatures ranging from 550 to 750 8C, and durations ranging from 90 to 150 s. Morphology and microstructure of granular thin films were characterized by atomic force microsc…
Photonic crystals are metamaterials designed to display a periodic modulation of the refractive index. [ 1,2 ] For light wavelengths that match the Bragg condition, such materials display a photonic gap. For suffi cient refractive index contrast, a complete band gap emerges, the density of states in the gap is zero,transmission vanishes and incident light is specularly refl ected.The concept wa…
The periodic nanostructuring of inner part of semiconductors can be successfully accomplished by the infrared ultrashort pulse laser with a double pulse configuration. Self-organized nanostructures inside semiconductor could be induced empirically only if it is indirect band gap semiconductor.The strained silicon regions with a width of about 100 nm are self-aligned parallel to the polarization…
We present 10-nm thick metal alloys created by coevaporation of calcium and silver as transparent top electrode for inverted bulk heterojunction small-molecule organic solar cells (SMOSC). It is shown that such alloys exhibit sufficiently high conductivity to replace previously used thicker (>14 nm) pure Ag contacts. At the same time, Ca:Ag alloys have higher transmittance compared to pure Ag, …
The use of engineered nano-sized materials led to revolutionary developments in many industrial applications and in the medical field. These materials, however, also may cause cytotoxicity. In addition to size, surface properties and shape were identified as relevant parameters for cell damage. Cell damage may occur as disruption of membrane integrity, induction of apoptosis and by organelle d…
In this work, we report on the prototyping of thin-film silicon tandem solar cells with periodic light-trapping textures. Our approach combines an industrial applicable nano-imprint process,for the fabrication of advanced light management concepts, with state-of-the-art thin film silicon solar cell technology. In a joint experimental effort between project partners of the European thinfilm sili…
Infrared plasmonic filters, consisting of subwavelength hole arrays etched into metal films, exhibit characteristics that are typically associated with the formation of surface plasmon polaritons, namely enhanced transmission and wavelength filtering of the incident light. In this article, the properties that dictate the plasmonic response of a material from the optical to the infrared regime a…
Upconversion (UC) enables the conversion of lower energy to higher energy photons and has gained interest for the application in solar cells and nanocrystal biolabels. Er 3+ -doped Gd 2 O 2 S is a highly promising UC material for applications. A record UC quantum yield of 12% was recently measured in Gd 2 O 2 S doped with 10% Er 3+ upon monochromatic excitation into the 4 I 13/2 state at 1510 …
The main challenge for applying upconversion (UC) to silicon photovoltaics is the limited amount of solar energy harvested directly via erbium-based upconverter materials (24.5 W m –2 ). This could be increased up to 87.7 W m –2 via spectral concentration. Due to the nonlinear behavior of UC, this could increase the best UC emission by a factor 13. In this paper, the combined use of quantu…
One dimensional gratings patterned on the surface of nanocrystalline titania electrodes are used as a light harvesting strategy to improve the overall performance of dye solar cells under both frontal and rear illumination conditions. A soft-lithography-based micromoulding approach is employed to replicate a periodic surface relief pattern onto the surface of the electrode,which is later sensi…
In the last decade in Europe, the power generated by Renewable Energy Sources (RES) has significantly increased. For the electric power system, the integration of a high amount of power generated by RES represents a big challenge. Energy Storage Systems (ESS) may help to solve problems related to the grid integration of RES. In this study, an analysis of the benefits that a planned and dedicate…
Most of the high efficiency kesterite solar cells are fabricated by vacuum or hydrazine-based solution methods which have drawbacks, such as high cost, high toxicity or explosivity.In our contribution, an alternative non-vacuum and environmental friendly deposition technology called electrostatic spray assisted vapour deposition (ESAVD) has been used for the cost-effective growth of Cu2ZnSnS4 (…
Periodic mesoporous organosilicas (PMOs) are unique materials with functional components embedded in their siliceous framework and have attracted much recent attention owing to their advantages over conventional mesoporous silica nanomaterials.[ 1 ] Such advantages include the homogeneous distribution of active functional sites throughout the whole framework,high loading of functional componen…
The application of layers of doped colloidal silicon nanocrystals sandwiched between hydrogenated amorphous silicon layers as emitters in silicon heterojunction solar cells is explored. It is shown that such emitters provide excellent interface passivation and reasonable conductivity. Final solar cells with such nanoparticle emitters reach conversion efficiencies on the same level as solar cell…
Electrically tunable mid-infrared metasurfaces with nanosecond response time and broad tuning range are reported. Electrical tuning is achieved by employing strong polaritonic coupling of electromagnetic modes in metallic nanoresonators with voltage-tunable inter-subband transitions in semiconductor heterostructures, tailored for a giant quantum-confi ned Stark effect.Experimentally, a 220-nm-…
An experimental apparatus has been developed to evaluate the drying process of green tea leaves. Tea drying is an energy-intensive process which results in the removal of leaf moisture; it is essential to the quality of the final product.In order to more efficiently use process energy, a prototype drying system has been built and tested. The prototype incorporates a rotating perforated drum whi…
In modern, stressed distribution system, voltage stability is a major concern from planning and operation perspectives. Remote wind farm connected to a weak distribution system through a long line could adversely affect the voltage stability of the respective distribution network. This paper investigates the transient and steady-state voltage issues of a distribution network with a distant dou…
In modern, stressed distribution system, voltage stability is a major concern from planning and operation perspectives. Remote wind farm connected to a weak distribution system through a long line could adversely affect the voltage stability of the respective distribution network. This paper investigates the transient and steady-state voltage issues of a distribution network with a distant dou…
In this study, we have exploited graphene’s unique combination of IR transparency and electrical conductivity to fabricate the fi rst pyroelectric IR sensor with graphene electrodes. We fi nd that the IR transparency of graphene enables an order of magnitude improvement in operating frequency, paving the way for faster thermal imaging than has been possible with pyroelectrics.Moreover, this i…
The application of PFSA-based proton exchange membranes was investigated for the production of hydrogen and sulfuric acid using a SO2-depolarized electrolyzer system. Parameters investigated included hot pressing pressure for the membrane electrode assembly (MEA) manufacturing, cell temperature, membrane thickness, catalyst loading, membrane type, and SO2 anode feed concentration.The effect of…
Realizing laterally continuous ultra-thin gold fi lms on transparent substrates is a challenge of signifi cant technological importance. In the present work,formation of ultra-thin gold fi lms on fused silica is studied, demonstrating how suppression of island formation and reduction of plasmonic absorption can be achieved by treating substrates with (3-mercaptopropyl) trimethoxysilane prior to…
Ultrastrong exciton–photon coupling of Frenkel molecular excitons is demonstrated at room temperature in a metal-clad microcavity containing a thin fi lm of 2,7-bis[9,9-di(4-methylphenyl)-fl uoren-2-yl]-9,9-di(4-methylphenyl)fl uorene. A giant Rabi splitting of Ω ∼ 1 eV is measured using angle-resolved refl ectivity and bright photoluminescence is observed from the lower polariton branch.…
Effi cient absorption of solar radiation is desired for the renewable energy sector, such as solar thermophotovoltaics and solar thermal applications.In order to minimize thermal re-radiation, wavelength-selective devices are required. Absorbers with structured surfaces are attractive because they derive their electromagnetic properties to a greater extent from their geometry and to a lesser e…